Washington -- Sen. Mary Landrieu's office Tuesday provided an explanation on why the senator and her husband owed about $1,200 in back property taxes and penalties for their Washington D.C. home: They thought they had paid the bill.

"Senator Landrieu and her husband believed that property taxes on their DC residence were paid in full by the required due date of Sept. 15, 2012," Landrieu spokeswoman Amber McDowell said in a statement. "They found out earlier this month that that wasn't the case, and have worked with their attorney to satisfy the outstanding balances. A final payment has been submitted to the DC government to resolve this issue."

On Monday, the tax bill for the Louisiana Democrat and husband Frank Snellings was first reported by the Daily Caller, an online news site founded by conservative commentator, Tucker Carlson.

In the article, The Daily Caller suggested that Landrieu is guilty of hypocrisy because she said just last week during a congressional hearing that "the reality" is "that the revenues coming in to the government are the lowest level since President Eisenhower was the president."

Landrieu was unavailable to comment Tuesday. She is leading a congressional trip to Asia this week that focuses on child welfare and adoption issues.